Deuteronomy* -- in effect the Constitution of the ancient Commonwealth of Israel -- contains several of the most extraordinary passages in all literature.
Perhaps chief among these is:
DT 31:16 . . . the LORD said to Moses: "You are going to rest with your fathers, and these people will soon prostitute themselves to the foreign gods of the land they are entering. They will forsake me and break the covenant I made with them. 17 On that day I will become angry with them and forsake them; I will hide my face from them, and they will be destroyed. Many disasters and difficulties will come upon them, and on that day they will ask, `Have not these disasters come upon us because our God is not with us?' . . . .
DT 31:19 "Now write down for yourselves this song and teach it to the Israelites and have them sing it, so that it may be a witness for me against them. 20 When I have brought them into the land flowing with milk and honey, the land I promised on oath to their forefathers, and when they eat their fill and thrive, they will turn to other gods and worship them, rejecting me and breaking my covenant. 21 And when many disasters and difficulties come upon them, this song will testify against them, because it will not be forgotten by their descendants. I know what they are disposed to do, even before I bring them into the land I promised them on oath" . . .
The song follows, in Ch 32 -- and is well worth the read.
Having recited it as a grim warning to the nation, Moses* then said: "Take to heart all the words I have solemnly declared to you this day, so that you may command your children to obey carefully all the words of this law. They are not just idle words for you--they are your life. By them you will live long in the land you are crossing the Jordan to possess." [Deut 32:46 -7, cf. ch 8:1 - 20, esp. vv. 17 - 20.]
How sad is it to then see, in Judges (outlining a pattern that repeated itself ever so many times in the History of Israel, ending up in repeated judgements culminating in the Babylonian Exile and the Roman Exile):
JDG 2:6 After Joshua had dismissed the Israelites, they went to take possession of the land, each to his own inheritance. 7 The people served the LORD throughout the lifetime of Joshua and of the elders who outlived him and who had seen all the great things the LORD had done for Israel . . . .
JDG 2:10 After that whole generation had been gathered to their fathers, another generation grew up, who knew neither the LORD nor what he had done for Israel . . . 12 They forsook the LORD, the God of their fathers, who had brought them out of Egypt. They followed and worshiped various gods of the peoples around them. They provoked the LORD to anger 13 because they forsook him and served Baal and the Ashtoreths. 14 In his anger against Israel the LORD handed them over to raiders who plundered them. He sold them to their enemies all around, whom they were no longer able to resist.
In brief, even growing up in the midst of an ongoing miracle of God, and hearing the miraculous story of your parents' lives is not enough to ward off a drift into forgetting God and breaking covenant. For, God has no grandchildren -- we must all individually come to know him for ourselves and learn walk with him ourselves.
Otherwise, in the teeth of even the most explicit warnings from God, we will drift away from him across time as new generations arise who know not God nor what he has done for our nations, and turn away from him in ingratitude and resentment over the moral restraints he puts on our behaviour. Never mind the telling force of Moses' wise counsel:
DT 10:12 And now, O Israel, what does the LORD your God ask of you but to fear the LORD your God, to walk in all his ways, to love him, to serve the LORD your God with all your heart and with all your soul, 13 and to observe the LORD's commands and decrees that I am giving you today for your own good?
So, while at first it may seem odd indeed to start exploring a theme on understanding our times in the interests of evangelisation of the nations by focusing on how nations turn away from God/apostasise, in fact, that is the very core of the matter.
For, as the early chapters of Genesis show both before and after the Flood, and as Rom 1 points out, the now pagan nations did not start out by not knowing God, but by turning their backs on and forgetting him. In short, paganisation and suicidal enslavement to clever images backed up by lies and out-of-control passions are the result of an earlier apostasy, one that probably took generations to have its full force:
RO 1:18 The wrath of God is being revealed from heaven against all the godlessness and wickedness of men who suppress the truth by their wickedness, 19 since what may be known about God is plain to them, because God has made it plain to them. 20 For since the creation of the world God's invisible qualities--his eternal power and divine nature--have been clearly seen, being understood from what has been made, so that men are without excuse.
RO 1:21 For although they knew God, they neither glorified him as God nor gave thanks to him, but their thinking became futile and their foolish hearts were darkened. 22 Although they claimed to be wise, they became fools 23 and exchanged the glory of the immortal God for images made to look like mortal man and birds and animals and reptiles.
RO 1:24 Therefore God gave them over in the sinful desires of their hearts to sexual impurity for the degrading of their bodies with one another. 25 They exchanged the truth of God for a lie, and worshiped and served created things rather than the Creator . . . . RO 1:28 Furthermore, since they did not think it worthwhile to retain the knowledge of God, he gave them over to a depraved mind, to do what ought not to be done. 29 They have become filled with every kind of wickedness, evil, greed and depravity. They are full of envy, murder, strife, deceit and malice. They are gossips, 30 slanderers, God-haters, insolent, arrogant and boastful; they invent ways of doing evil; they disobey their parents; 31 they are senseless, faithless, heartless, ruthless. 32 Although they know God's righteous decree that those who do such things deserve death, they not only continue to do these very things but also approve of those who practice them.
Now, too, we see a rising tide of apostasy in our own region coming from the North, where over the past 50 - 250 years the Europeans and North Americans have increasingly forgotten God. So, it is worth briefly pausing to amplify on vv. 19 - 20 by using the concept of inference to best explanation (or, the logic of abduction) to look at the force and implications of the evident design in the cosmos and in life, and the implicit trust we put in our minds and in core morality:
1] Quite often, we do not reason so much FROM facts TO conclusions they imply, but rather by "explaining" otherwise puzzling but credible facts in light of "the best" of competing hypotheses. To do so, we compare such alternative models or theories or explanations on  factual adequacy,  coherence, and  simplicity or elegance, i.e. a subtle balance between being simplistic on one hand or an ad hoc patchwork on the other. By adding abduction/IBE to our logical toolkit, we will enhance our ability to apply the better known approaches to reasoning, deduction and induction, as well. [Cf a useful elaboration here. Also, a discussion of the theological application of the concept here, in the context of cosmology.]
2] So, when we confront the starry sky and learn of the astonishing fine-tuning of the observable cosmos necessary for us to be here to so wonder, it drives us to ask: why? In turn, we can easily see that the live option alternatives are [a] that there is an in effect infinite material chaos that behaves at random and just happened to throw us up, or [b] that we are the product of an intelligent, purposeful, powerful designer. Of these, the first is an obvious piece of ad hoc patchwork that resorts to an inherently unobservable -- can we see infinity? -- metaphysical speculation [too often disguised to the public and scientists alike as "science"] to prop up a faltering evolutionary materialist view. The second is a classic and plainly abundantly well-supported inference to design on the scale of the universe.
3] Similarly, when we look in our bodies at the astonishing functionally specified complex information [FSCI] in the molecular machinery of the cell, starting with DNA, we find that neither natural regularities nor chance nor both in combination can explain either the origin of life or its massive diversity. The institutionally dominant evolutionary materialism fails again -- and on the evidence, sadly, many of its advocates are resorting to the classic stratagems of deceptive, rage-driven rhetoric and even to harassment of those who dare to question the dominant view.
4] Then, when we look within at our own minds, we find that we are forced to trust the capacity of our minds to in general perceive the world accurately, and to reason correctly. But, on evolutionary materialist premises, our minds -- without residue -- are produced and controlled by forces that would be utterly irrelevant to logic, truth or validity. Indeed, that is how such thinkers often dismiss their critics: we have had a bad potty training experience, we are constrained by our class-roots, etc etc. But, that logic cuts both ways: Sigmund, what of your potty training? Karl, what of your own class origins? B. F., are you not just yet another rat in the cosmic maze? And so on. This is a classic self-referential inconsistency. [Cf Plantinga's longer discussion here.] So, if we must trust our minds, we need to accept an alternative view that leads to and coherently explains how we have generally trustworthy [though of course sometimes error-prone] minds!
5] Finally, on morals, many atheists think that e.g. the problem of evil is a knockout blow to the notion of an all-good, all-knowing, all-powerful God. But to think like that, they show that they are simply not current, given the acknowledged force of Plantinga's famous Free Will defense: as long as it is logically possible for God to use the potential for evil to create a higher good, the existence of God is not at all disproved by the actual existence and extent of evil we see. And, so long as the existence of virtues such as love - the queen of all virtues -- require the power of choice, evil is possible.
6] But also, they fail to see a key but implicit self reference. For, we should ask: why is evil real, significant, painful and offensive? To answer that, we must accept the reality of the moral, which immediately means that we accept that the world has in it entities that are real and true but are beyond the reach of empirical sciences: reality is not to be equated with physical existence, and knowledge is not locked up to the products of the empirical sciences. Then, since evil specifically violates our sense of obligation to justice/fairness and rights, we must ask: whence do these come and why are they so important? To that, the only defensible answer is: God is the foundation of morality.
In short, Paul was dead right to say in Rom 1:20 that since the creation of the world God's invisible qualities--his eternal power and divine nature--have been clearly seen, being understood from what has been made, so that men are without excuse.
But, equally, if we refuse to acknowledge of be thankful to our gracious, loving, provident Creator, we will be tempted to make up clever stories to explain away uncomfortable evidence that points to him, and turn away to images and myths that lead us astray, becoming endarkened in mind rather than enlightened and falling prey to out-of-control, self- and socially- destructive, often perverted passions. That,plainly is the story of the lands of the North in our day, and surges from that tidal wave have been hitting our region with increasing frequency and force over the past several decades.
So, will we now insist on knowing God in the face of Jesus for ourselves? Will we counter the clever lies and temptations that would lure so many of our people astray from God? And, will we in turn go back to the lands of the North -- from which the missionaries who blessed us with the Gospel originally came -- to remind them of Him whom they are so busily forgetting?
If not now, then, when? If not here, then, where? If not us, then, who? END
* NB: It is common nowadays to dismiss the five books of Moses through the Documentary/JEDP Hypothesis and the like. However, that selectivley hyperskeptical hypothesis has long been untenable, not least because it originally started from the notion that writing had not been invented in Moses' day and because it depends crucially on a pre-supposed, imposed Hegelian view of the evolution of religions, from "lower" to "higher." Indeed, it is worth noting how the early and current proponents of this view and other linked or derived skeptical/liberal theological ideas have consistently dismissed the force of relevant archaeological evidence that is best explained as being consistent with the substantial credibility of the traditional view of the OT and NT. Cf discussion here.